1. Field of the Invention
The present invention relates to a laser processing method and a method for manufacturing a light-emitting device.
2. Related Background Art
Techniques for highly precisely cutting a wafer having a multilayer structure in which a semiconductor operation layer made of a group III-V compound semiconductor such as GaN is grown as a crystal on a single-crystal sapphire substrate have recently been demanded for manufacturing semiconductor light-emitting devices such as semiconductor laser devices and light-emitting diodes.
For cutting a wafer having such a multilayer structure, blade dicing or diamond scribing has conventionally been used in general.
The blade dicing is a method of cutting the wafer by incising it with a diamond blade or the like. On the other hand, the diamond scribing is a method in which a diamond point tool forms a scribe line on the front face of the wafer, and a knife edge is pressed against the rear face of the wafer along the scribe line, so as to break and cut the wafer.
For example, Japanese Patent Publication No. 2780618 and Japanese Patent Application Laid-Open No. 2001-156332 disclose semiconductor light-emitting devices formed by combining such blade dicing and diamond scribing together.